U.S. Pat. No. 5,361,315 discloses an optical switch comprising: a refractive element between a reflector and multiple optical waveguides, the refractive element being pivotable to a first position to optically couple a first set of the waveguides, and the refractive element being pivotable to a second position to optically couple a second set of the waveguides. Each set of waveguides is optically coupled by light being transmitted from one waveguide of the set to another waveguide of the set.
The waveguides are required to be positioned at a desired focus from the reflector. A need exists for an adjustment mechanism to adjust the position of the reflector focus in front of the waveguides.